(PU) Elastomer ya Polyurethane Yosatopa, Yotentha Kwambiri, Yodzichiritsa Yokha: Yopangidwa kudzera mu Dynamic Covalent Adaptive Network Yochokera ku Ascorbic Acid

Ofufuza apanga polyurethane elastomer yatsopano yochokera ku ascorbic acid-derived dynamic covalent adaptive network (A-CCANs). Pogwiritsa ntchito mphamvu ya keto-enol tautomerism ndi dynamic carbamate bonds, zinthuzo zimapeza mawonekedwe apadera: kutentha kwa kutentha kwa 345 °C, kupsinjika kwa fracture kwa 0.88 GPa, mphamvu yokakamiza ya 268.3 MPa (mphamvu yoyamwa ya 68.93 MJ·m⁻³), ndi mphamvu yotsalira pansi pa 0.02 pambuyo pa ma cycle 20,000. Imadziwonetsanso yokha mkati mwa masekondi ndi mphamvu yobwezeretsanso mpaka 90%, kupereka yankho lopambana pakugwiritsa ntchito zida zanzeru ndi zida zomangira.

Kafukufuku wodabwitsa uyu adapanga netiweki yosinthika ya covalent (A-CCANs) pogwiritsa ntchito ascorbic acid ngati maziko omangira. Kudzera mu keto-enol tautomerism yokonzedwa bwino komanso ma dynamic carbamate bonds, elastomer yapadera ya polyurethane idapangidwa. Zipangizozi zikuwonetsa kukana kutentha kofanana ndi polytetrafluoroethylene (PTFE)—ndi kutentha kwa kutentha kofika 345 °C—pomwe zikuwonetsa kulimba kwabwino komanso kusinthasintha: kupsinjika kwenikweni kwa 0.88 GPa, komanso kuthekera kosunga kupsinjika kwa 268.3 MPa pansi pa 99.9% compression strain pamene imatenga 68.93 MJ·m⁻³ ya mphamvu. Chodabwitsa kwambiri, chipangizochi chikuwonetsa kupsinjika kotsalira kosakwana 0.02% pambuyo pa makina 20,000, kudzichiritsa mkati mwa sekondi imodzi, ndikukwaniritsa mphamvu yobwezeretsanso ya 90%. Njira yopangira iyi, yomwe imakwaniritsa mwambi wakuti "kukhala ndi manja a nsomba ndi chimbalangondo," imapereka yankho losintha kwambiri pa ntchito monga zovala zanzeru komanso zipangizo zotetezera ndege, komwe mphamvu ya makina komanso kulimba kwa chilengedwe ndizofunikira kwambiri.